Fluid controlled variable output pump



Nov. 3, 1964 G. R. FUNK FLUID CONTROLLED VARIABLE OUTPUT PUMP Filed Aug. 17, 1959 INVf/l/flk' 671. 5527' P. FUNK United States Patent M 3,155,042 FLUKE CGNTRQLLED VARIABLE OUTPUT PUMP Giihert R. Funk, Wauiresha, Wis., assignor to Waukesha Foundry (Iornpany, Wauuesha, Wis, a corporation of Wisconsin Fiied Aug. 17, 195%, Ser. No. 834,229 16 Ciaims. (Cl. 10342) This invention relates to a fluid controlled variable output pump.

There are great advantages in having a motor-driven pump which will operate at a constant speed but has means for infinite variation of its output. A device for that purpose was patented to me, No. 2,636,440, on April 28, 1953. The present invention represents an improvement having the advantage of very sensitive control which may be remote if desired and requires no tools for its operation.

A source of fluid under high pressure communicates through a reducing valve of conventional design with a floating piston guided within a prefabricated and separately sealed cylinder sleeve for movement to and from a seat across the two legs of a bypass port. For this purpose, the piston is preferable to the diaphragm disclosed in my former patent.

The reducing valve has an easily manually-controllable handle and may be located at a point remote from the pump, if desired. Any setting fixed by the handle of the reducing valve will result in subjecting the valve piston to a corresponding pressure effective in regulating bypass flow around the pump, thereby controlling its output with infinite variability throughout the range.

In the drawings:

FIG. 1 is a view largely in side elevation and partially broken away in transverse section through a pump, showing a complete motor-driven pump embodying the invention.

FIG. 2 is a view taken in section on the line 22 of FIG. 1.

FIG. 3 is a View taken in section on the line 3-3 of FIG. 1, portions of the device being shown in side elevat1on.

The motor 5 is operatively connected to drive the shaft 6 and the shaft '7 of a conventional type pump having intermeshing lobes. The two shafts are connected by gears S and 9 to rotate in unison. The runner 10 on shaft 6 carries lobes 11 while the runner 12 on shaft 7 carries lobes 13. The pump casing 15 has inlet and outlet chambers 16 and 17 with which supply pipe 18 and discharge pipe 19 respectively communicate. The pump casing 15 has a detachable head at 20 provided with passages 21, 22 opening to a seating face at 23 encircled by an annular flange 24 integral with the head portion 20 of the casing.

Within this annular flange is a cylinder sleeve 25 shouldered at 26 to engage the ends of the flange. Some such packing as the O-ring shown at 28 provides a seal between the cylinder sleeve and the flange. The cylinder sleeve is held in place by a threaded cap 22 to which the pressure line 39 communicates with the interior of the cylinder sleeve.

The abutting piston is reciprocable in the cylinder sleeve and is peripherally channeled to receive the packing ring 36 which may be another O-ring. When the piston is in the position shown in FIG. 2, it seats upon the surface 23 to close both of the ports or passages 21, 22 to preclude communication of one passage with the other. The floating piston may be urged to its passageclosing position by fluid pressure communicated to it through the line 30. The amount of such pressure will determine the point at which the pressure will be overcome by pressure in that passage or port which communi- 3,l55,fl42 Patented Nov. 3, 1964 cates with the chamber 21 or 22 at the outlet side of the pump. (The pump is fully reversible so that either chamber and either passage may be carrying the pressure, the other being subject to partial vacuum.) When the pressure on the inner face of the piston exceeds the fluid pressure to which the external face or" the piston is subject, the piston will open until the pressures equalize. Thus the fiow between the ports or passages 21 and 22 will always be proportioned to the pressure differential. Inasmuchas the pump is intended for operation at a substantially constant rate, any variation in differential is the result of an increase or decrease of the fluid pressure communicated to the outer face of the piston through the line 30.

The line 30 is supplied with pressure through the reducing valve 38 of the pressure tank 39. The gauge 43 is optional. The valve has a manually operable handle 41 and may be of any conventional or desired design. The valve either is a four-way valve so that the pressure to which the floating piston is subject may be decreased as readily as it may be increased, the excess simply being vented to the atmosphere, or there is a minute bleed port 45 anywhere in the portion of the system beyond the valve. As shown, this port is in the end cap 29 of the cylinder (FIG. 2).

While reference has been made to fluid pressure, it will be understood that the simplest and easiest control is eflected by using a gas as the fluid, compressed air or compressed carbon dioxide being examples of readily available gases which may be used for the purpose.

The compressed fluid source 39 may either be assembled unitarily with the pump and motor or may be at a remote point, one of the advantages of the present system consisting in the fact that almost no power is required for manual operation of the valve handle 41 and it is unnecessary for the operator to use tools or even to go to the pump when it is desired to change the output.

It will be observed that the floating piston 35 is rigid throughout the area of the face 43 which serves as a valve. The contours of the face 43 in relation to the valve seat surface 23 will determine the relative coefficient of flow as the valve opens, both surfaces being shown as planiform for the purpose of the present disclosure. Whatever the contours of the respective surfaces in cross section, the relative contours do not change as the valve opens or closes. The range of movement permitted the floating piston 35 within the prefabricated cylinder sleeve 25 is desirably suflicient to accommodate bypassing the entire output of the pump if so desired.

I claim:

1. In a pump having a seat and provided with inlet and outlet bypass ports opening to said seat, the combination with, a floating valve and piston movable to and from the seat, a cylinder in which said piston is reciprocable, a source of fluid under pressure, said source being independent of said pump, and manually operable fluid pressure control means for variably subjecting the floating piston to pressure from said source in varying amount.

2. In a pump having displacement means and inlet and outlet bypass ports and a seat to which said ports open, the combination with piston valve means movable to and from said seat for controlling communication between said ports and means for variably biasing said valve means and including a cylinder in which said piston valve is reciprocable, said piston valve having packing engaging the cylinder, means independent of said pump for providing a source of fluid under pressure, and fluid pressure connections from the source to the cylinder and including a manually operable pressure regulating valve for controlling the amount of pressure communicated from said source to said cylinder, the first mentioned valve means being subject to such pressure for varying the differential pressure with which it seats.

3. In a liquid pump having displacement means and bypass ports and a seat to which said ports open, the combination with said seat, of a floating piston having a valve face and reciprocable to and from the seat, cylinder means in which the floating piston is reciprocable, a separate supply of gas under pressure, and means for delivering variably controllable gas pressure from said supply to said cylinder means for biasing said piston.

4. The device of claim 3 in which said seat is provided with an annular flange, the cylinder means comprising a prefabricatedring telescopically positioned Within the flange, a cap connected with the flange and engaging the ring, the means for supplying variably controllable pressure including a line communicating through said cap with the interior of said ring.

57 The device of claim 4 in further combination with packing between the ring and the flange and packing between the piston and the ring.

6. The combination with means providing a ported seat and a valve comprising a piston movable to and from contact with said seat to close and open said port, of an annular flange about the seat, a prefabricated cylinder sleeve telescopically engaged within the flange and having a shoulder seating on the end of the flange, a retainer connected with the flange and securing the sleeve with its said shoulder abutting: the end of the flange, the piston valve being reciprocable Within said cylinder sleeve.

7. The device of claim 6 in which said cylinder sleeve has a packing interposed between it and said flange intermediate the said seat and the said shoulder.

8. In a pump having displacement means and inlet and outlet bypass ports and a seat to which said ports open, the combination with a cylinder, a piston valve having a face and movable in said cylinder to and from face contact with said seat for controlling communication between said ports and having a packed fit in said cylinder, infinitely variable means differentially effective for controlling the movement of said piston valve respecting said seat, and remote control mechanism for varying the eflect of said variable means on said valve, said mechanism including .a freely oscillatable handle whereby said ports may be controlled from a remote point without the use of tools.

9. The combination set forth in claim 8 in which said remote control mechanism comprises a source of fluid pressure independent of said pump, and a pressure reducing valve having manually operable means provided with said handle, said pressure reducing valve being connected with said cylinder whereby fluid pressure from said source will directly act on said piston valve for moving it toward said seat.

10. In a pump having displacement means and a casing 4 therefor including inlet and outlet by-pass ports and a seat through which said ports open, the combination with said casing of an annular flange integral with the casing and surrounding the seat, a prefabricated cylinder sleeve telescopically disposed within the flange, a retaining cap connected with the flange and engaged with the cylinder sleeve and constituting means for securing the sleeve within the flange and for closing the outer end of the sleeve, means providing a fluid pressure connection through said retainer cap, and a piston valve reciprocable within the cylinder sleeve to and from the seat and subject to pressure communicated thereto through said rctainer cap, and means for supplying fluid pressure variable in amount through said connection. to actuate said piston valve toward said seat, said valve being subject through one of said ports to pressure developed within said casing by said displacement means for actuating said valve away from said seat, the valve being floated for movement in response to pressure differential between the pressure developed by the displacement means and the variable pressure communicated through the connection in said cap.

References (Jited in the file of this patent UNITED STATES PATENTS 623,934 Wilson et al. Apr. 25, 1899 915,204 Montgomery Mar. 16, 1909 1,284,662 Halliwell Nov. 12, 1918 1,346,123 Guerrlich July 13, 1920 1,625,780 Atkins Apr. 26, 1927 1,649,356 Louis Nov. 15, 1927 1,676,999 Mobley July 10, 1928 1,989,891 Sprado Feb. 5, 1935 2,054,640 Stenger Sept. 15, 1936 2,243,711 Lamb May 27, 1941 2,397,443 Statham Mar. 26, 1946 2,405,466 Tabb Aug. 6, 1946 2,411,574 Hunt Nov. 26, 1946 2,417,474 Feroy Mar. 18, 1947 2,420,052 Muir May 6, 1947 2,449,382 Huber Sept. 14, 1948 2,580,030 Lee Dec. 25, 1951 2,586,147 Caserta Feb. 19, 1952 2,636,440 Funk Apr. 28, 1953 2,638,927 Walker May 19, 1953 2,642,001 Dale et a1 June 16, 1953 2,700,339 Schmitt Jan. 25, 1955 2,728,547 Crookston et al. Dec. 27, 1955 2,786,553 Boone et al Mar. 26, 1957 2,829,664 Mountford Apr. 8, 1958 2,856,957 McDowall et al. Oct. 21, 1958 2,915,976 Demtchenko Dec. 8, 1959 FOREIGN PATENTS 384,412 Great Britain Dec. 8, 1932 

1. IN A PUMP HAVING A SEAT AND PROVIDED WITH INLET AND OUTLET BYPASS PORTS OPENING TO SAID SEAT, THE COMBINATION WITH, A FLOATING VALVE AND PISTON MOVABLE TO AND FROM THE SEAT, A CYLINDER IN WHICH SAID PISTON IS RECIPROCABLE, A SOURCE OF FLUID UNDER PRESSURE, SAID SOURCE BEING INDEPENDENT OF SAID PUMP, ANDMANUALLY OPERABLE FLUID PRESSURE CONTROL MEANS FOR VARIABLY SUBJECTING THE FLOATING PISTON TO PRESSURE FROM SAID SOURCE IN VARYING AMOUNT. 